Color marking engines capable of printing non-overlapping additive colorants (red, green, blue), such as the Kodak ImageSource 70 C/P electrophotographic color printer are known. Previously such color marking engines have not been used to print multicolor images such as photographs because the printers were not believed capable of producing commercially acceptable image quality. They were used as accent color printers which could produce only a limited number of colors.
Normally color printers employ cyan, magenta, yellow and black to produce color prints. By overlaying these colorants, it is possible to make most colors. These printers are often called process color printers.
Accent color printers can place several colorants on the page. Since they cannot overlay colorants, they can only make colors which are shades of the available colorants plus white if the print receiving medium is white, or the underlying color of the print receiving medium if it is not white. Accent color printers are typically cheaper to manufacture than process color printers.
From the forgoing, it can be seen that it would be advantageous to have a method of extending the gamut of colors printable by an accent color printer, and in the event that the color printer is supplied with a set of three primary colorants, for printing most of the colors currently printable with process color printers.